The present invention relates to a method for displaying an absence-message in a private exchange system, and more particularly, to a method for displaying to a calling party, messages concerning a reason for the absence and the period of absence of a called party when the calling party attempts to contact an absent called party ("a party" may also be referred to as a "subscriber").
Generally, in a keyphone system, when a party B is talking on the telephone with another party, say A, and an incoming call is received from another party, say C, the method for processing the message is that party B recognizes party C's call by a blinking message lamp on his telephone indicating that the current line is in a busy state. Party C then presses a message key on her telephone so that the keyphone system retains her call on hold to wait for party B to finish his current conversation. After party B finishes talking with party A, he then presses a message key and the keyphone system connects him to speak with party C. If party B is not actually on the telephone however, but rather is away from his desk, party C will have to wait for his return or call back later.
In the above scenario, it is often inconvenient and a waste of time for the calling party to continuously wait or attempt to re-call the called party. A large reason for this problem is because the calling party is unaware of the called party's period of absence. If the calling party knew the called party had been absent for a long period of time, it may suggest that a continued absence is likely, and therefore it would be unwise to wait or immediately re-call. On the other hand, if the calling party knew that the called party had been absent for only a short period of time, it may suggest that the called party had only stepped away for a moment, and therefore it would be prudent to wait or re-call within a short time. In the art there have been several attempts to provide a system that communicate messages to a calling party when a party being called is either absent or unavailable.
One earlier such attempt is disclosed in U.S. Pat. No. 5,029,198 entitled Telephone Call Responding System and Control Method and Device Therefore issued to Walpole, et al. In Walpole '198, a called party, upon receiving an incoming telephone call, selects one of a plurality of call response messages by actuating a control key. This activates the system to provide a synthesized speech message to the calling party which gives the caller a desired message. The disadvantages of this system, however, are that it requires the called party to be present at the time of the incoming call, and further that it provides only a voice message to the calling party. The system does not provide the caller with a visual message at his telephone. Accordingly, this system is deficient because it fails to provide a message for a called party who is absent, and also fails to provide its message in a format compatible for a visual display.
An earlier attempt at a message transferring system is disclosed in U.S. Pat. No. 4,969,182 entitled Method of Telephone Call Wherein Status Data Inhibits Calls And Indicates To The Caller The Reason The Called Party Is Unavailable, issued to Ohtsubo, et al. In this system, a party registers a message indicating a reason for his absence with an electronic switching unit. When an incoming call arrives for the party, the switching unit decides whether the party's telephone is available to call on the basis of the registered message. If a message has been registered by the party, a calling party is informed of the message by an audible signal or a visual display. Although this system may address some of the disadvantages associated with Walpole, et al. '198, by not requiring the called party to be present during an incoming call and by providing a visual display for the caller, it has been my observation that Ohtsubo '182 suffers from the deficiency of not supplying the caller with information regarding the called party's term of absence. Therefore, even though the calling party will know the reason for the called party's absence, I have observed that the calling party will not be aware of how long the called party has been gone or even provided with any indication of how long the absence is expected to continue. Accordingly, it would seem to me that the calling party will have no idea as to when he should attempt to call back.
A more recent also incomplete attempt at solving the above-mentioned problems is disclosed in U.S. Pat. No. 5,119,415 entitled Method of Displaying Called Party Information On Calling Party Terminal And Communication Network Using The Method issued to Aoyama. In this effort, a party registers a message in an exchange system. Then, when an incoming call arrives, the registered message is displayed on a terminal of the calling party. It has been my observation that the displayed message however includes only a content message and an estimated return time and that the message does not provide information regarding how long the party as been absent. Therefore, it would seem to me that if by accident or oversight, the called party fails to return by the displayed time, the caller has no other indication as to when the called party might return. For instance, if a party registers a message indicating that he will be on a "business trip" until Mar. 15, 1994, and on Mar. 17, 1994, he has not returned, a calling party may be entirely clueless as to when arrival is expected. In response, the calling party may continue to repeatedly attempt to telephone the absent party over an extended period of time in expectation of the return of the called party. Depending upon when the party actually returns, these continued attempts by the calling party may be extremely inconvenient and an extraordinary waste of time.